rober



(Nn Model.) 2 sheets-sheet 1.

B. ROBER. STEAM BOILBR FURNAGE.

Ijyfs lm Ey WAHMMH] Patented Peb. 13

NoI 514,497.

(No Model.) 2 sheetssheen f2. B. ROBER.

, STEAM Boum PURNAGB. No. 5l4,497. Patented Feb. 13, 1894.

11 l '0N 2 2- C E D y [L B h' Y 3 Nrrnn STATES VPara eric.

STEAM-BOILER FU RNAGE.

SIECIFICATION forming part of Letters Patent No. 514,497, dated February 13, 1894.

Application filed December 4, 1893. Serial ll'o. 492,754. Cdc model.)

To all whom, it may con-cern:

Be it known that I, BERNHARD RBER, civil engineer, a subject of the Emperor of Germanygesiding at Dresden, Germany, have invented certain new and useful Improvements in Furnaces and Boilers for Steam-En- `gilles, of which the following is a specificaion.

O ne part of my invention relates more especially to the fire-box; its objects are to obtain a large heating-surface, and to protect the casing and jacket; which ends Iattainby incasing the fire-box with brick-work, and surrounding it with water-tubes partly incased in the brick-work so as to protect it and be protected by it. i

.lily improvement further consists in combining with water-tubes surrounding the fire box and passing through the tube-sheet, other water-tubes projecting through the tube-sheet into the fire-box, below the surrounding tubes, to obtain increased heating-surface without obstructing the draft, and also to protect the bridge over which the air passes on its way to the fire tubes.

My improvement further consists in surrounding the top and sides of the fire-box with water-tubes extending through the tube-sheet into the boiler; brick-work partly incasing these tubes, and an outerjacketinclosing the brick-work, so as toleave an airspace between the brick-work and jacket through which air passes to the fire-box.

My improvements further consist in other combinationsof instru mentalities hereinafter specified.

The accompanying drawings show so much, only, of apparatus embodying my improvements in the best way now known to me, as is necessary to illustrate the subject-mattei' herein claimed.

Some of my improvements may be used without the others and in apparatus differing somewhat in its details of construction from those herein shown. Unless otherwise indicated the parts are of usual well known construction and operation. The furnace end l term the rear, andthe opposite end, the front of the apparatus.

Figure 1 represents avertical transverse section through the apparatus, on the line 11, of Fig. 2, which in turn represents a vertical section therethrough, on the line 2 2, of the preceding figure. Fig. 3 shows a transverse section on two different horizontal planes through one side of the apparatus, on the line 3--3 of Fig. 2. These figures show my improvements as more especially adapted for a boiler of the locomotive type. Fig. 4 represents a vertical transverse section on the line 4th-4; of Fig. 5, which in turn shows avertical longitudinal section through one side of the apparatus, on the line 5-5 of Fig. 4. These iigures show my improvements as embodied in a stationary boiler. Fig. G is a detail view on an enlarged scale of one form of water tube which may be employed, and Fig. 7 is an end View thereof.

I will first describe my improvements with especial reference to Figs. l, 2 and 3, beginning with the furnace or fire-box A, which is shown as surrounded by an inclosing casing B, of hre-brick or equivalent material, inclosed in an enveloping jacket C, far enough from the casing to leave an air-space D, between the jacket and casing. or dampers c, in the jacket regulate the admission of Vair to this space, which communicates with the tire-box so as to draw the air heated in the space into the furnace to promote combustion of the fuel, the overheating of the jacket being at the same time prevented.

Fuel is fed to the furnace `by means of a feed-screw E, somewhat like that shown in Letters-Patent No. 205,428, granted to me June 25,1878, as assignee of AugustL. Schultz but actuated in a different way. lt is shown as operated intermittingly, or with a step-bystep movement through the intervention of an eccentric f,`on a rotating shaft F, of the engine, sliding endwise in bearings under the lire-box and vibratin g an elbow-lever F', rocking vertically on a pivot j', and actuating a pawl f-,engaging with a ratchet-gear F2, on the shaft of the feed-screw E.

The grate-'bars G are arranged lengthwise of the furnace; their ends lying below the feed-door-being horizontal for a short distance and then sloping downward to the other end of the lire-box, (see Fig. 2.) The fuel is thus iirst fed onto the horizontal part of the gratebars, audthen slides down their inclined portion, air being admitted both above Valves, slidesand below the grate. The result of this organization is that the fuel accumulates or piles up on the horizontal part of the grate, where it is coked, and then slides down the inclined part in a layer of gradually diminishing thickness. Air being freely admitted at the lower end of the bars creates a bright hot flame, which aids in consuming the gases, evolved near the feed door. To aid in burning these gases, an additional air-inlet g, is provided between the air-space and furnace, some distance above the grate; the iniiux of air therethrough bein g regulated by a valve g controlled bya gear-wheel and screw-rod G.

The sides and top of the fire-box are provided with longitudinal water-tubes H, partly embedded in or surrounded on three sides by the brick-work casing, (see Fig. l.) These tubes are double, the outer ones h, being closed at the front or feed-end, and passing through the front head of the furnace, while the rear ends are open and project through the tube-sheet I, into the boiler J, which is filled with the usual re-tubesy`. The inner water-tubes h', are open at both ends and extend from near the front end of the outer tubes h, in which they are inclosed and concentrically arranged, through the tube-sheet into the boiler; thus keeping up a rapid circulation of the water therethrough. Similar tubes h2, project from the boiler into the firebox a short distance, and are likewise partially incased in tire-brick, (see Fig. 2,) thus promoting circulation in the lower part of the boiler.

By the construction above described much additional evaporating surface 'is obtained, and the casing protected withoutinterfering with access of the products of combustion to the fire-tubes of the boiler, which may be of approved locomotive type. The water-tubes, it will be observed, are arranged outside of the circle of the fire-tubes, so as not to obstruct the draft, the brick-work being correspondingly widened out or thinned at that point, which may safely be done, as the water-tubes protect it.

By employing water-tubes such as shown in Fig. 6, an improved circulation is eected. As there shown, the outer or rear end of the outer tube h is closed, as it is in the arrangement shown in Fig. 2. The inner end of the inner tube h is open, its opposite end being slightly curved and projecting into the water-space of the boiler. Partition walls h3 are employed to form passages to the four ports or openings l, 2, 3, 4. These partition walls meet at their inner and outer ends, and surround the ports. The passages 5 and 6, between the partitions, are in communication with the waterfspace of the boiler, while the passages 7 and 8 communicate with the inner tube h. That is to say, water entering from the water-space of the boiler, enters the tube h', through the ports 1 and 2, as shown by feathered arrows. It passes to the rear, open end of the tube h', as shown by the arrows, then takes the direction shown by the plain arrows, and enters the ports 3 and 4, passing through the tube h out to the waterspace of the boiler. The su per-heated water or steam rises to the top of the tube 72,', while the cooler portion of the vwater moves at the bottom. By this difference of temperatures, a circulation is kept up and there is great economy of heat. The tire-brick forming the bridge wall are preferably constructed and arranged as shown in Figs. l and 2. As there shown, there are five blocks X, provided Wlth openings g, through which the tubes of the bridge extend. The blocks are fitted close together, and are supported on the tubes. Air enters through the openingsin theblocks below the tubes, and passes over the tops of the blocks into the fire-tubes. This is an economical arrangement; it is strong and durable, and may readily be repaired.

What I claim herein as new and of my own invention is- 1. The combination substantially as hereinbefore set forth, of the boiler, the re tubes arranged therein, a fire box communicating with the tire tubes, water tubes closed at their rear ends and surrounding the tops and sides of the fire box, and passing through the tube sheet around the ends of the tire tubes.

2. The combination, substantially as hereinbefore set forth, of the fire box, brick work incasin g the fire box,water tubes closed at one end and surrounding the top and sides of the IOO fire box, and passing through the tube sheet of the boiler, and tire tubes passing through the tube sheet and having their ends surrounded by the water tubes.

3. The combination, substantially as hereinbefore set forth, of the tire box, having brick work extending over it, and a shell arranged around the brick work, a boiler, water tubes communicating with the -boiler extending over the re box under the brick work and through the back sheet of the fire box, said water tubes being each closed at its outer end, and provided with an inner tube open at both ends, for the purpose specified.

4. The combination, substantially as hereinbefore set forth, of a tire-box, water-tubes arranged in the fire-box, and passing through the tube-sheet to the boiler, and short watertubes projecting through the tube-sheet into the fire-box below the fire-tubes, for the purpose specified.

5. The combination, substantially as hereinbefore set forth, of a fire-box, atube-sheet, a bridge wall, and short water-tubes leading from the water-space of the boiler and arranged under the bridge wall.

6. The combination, substantially as hereinbefore set forth, of a fire-box,a bridge wall composed of perforated blocks, water-tubes extending through the perforations of the blocks, and air-inlets through the blocks below the tubes.

7. The combination, substantially as here inbefore set forth, of a fire-box incased in IIO brick-work, water-tubes surrounding the top and sides of the fire-box and partly inclosed in the brick-Work, and a jacket inclosing the brick-Work so as to leave an air-space through which air may pass to the fire-box, for the purpose specied.

8. The combination, substantially as hereinbefore set forth, of the lire-box, its inclosing brick-work, longitudinal Water-tubes partly ineased in the brick-work, a jacket inclosing the brickwork so as to leave an air-space botween the jacket and brick-Work, and valves regulating the admission of air through the air-space to the' furnace or fire-box.

9. The combination, substantially as hereinbefore set forth, with a fire-box, of a series of circulating tubes, each comprising an outer tube, with one end closed, and an inner tube with both ends open, partitions between the BERNHARD RBER.

Witnesses:

LLOYD B. WIGHT, BEssiE W. MILLER. 

